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#if NET20 || NET30 || !NET_4_6
// Copyright (c) Microsoft. All rights reserved.
// Licensed under the MIT license. See LICENSE file in the project root for full license information.
using System.Diagnostics;
using System.Dynamic.Utils;
namespace System.Linq.Expressions.Reimplement
{
/// <summary>
/// Emits or clears a sequence point for debug information.
///
/// This allows the debugger to highlight the correct source code when
/// debugging.
/// </summary>
[DebuggerTypeProxy(typeof(DebugInfoExpressionProxy))]
public class DebugInfoExpression : Expression
{
private readonly SymbolDocumentInfo _document;
internal DebugInfoExpression(SymbolDocumentInfo document)
{
_document = document;
}
/// <summary>
/// Gets the static type of the expression that this <see cref="Expression" /> represents. (Inherited from <see cref="Expression"/>.)
/// </summary>
/// <returns>The <see cref="Type"/> that represents the static type of the expression.</returns>
public sealed override Type Type
{
get { return typeof(void); }
}
/// <summary>
/// Returns the node type of this <see cref="Expression" />. (Inherited from <see cref="Expression" />.)
/// </summary>
/// <returns>The <see cref="ExpressionType"/> that represents this expression.</returns>
public sealed override ExpressionType NodeType
{
get { return ExpressionType.DebugInfo; }
}
/// <summary>
/// Gets the start line of this <see cref="DebugInfoExpression" />.
/// </summary>
public virtual int StartLine
{
get { throw ContractUtils.Unreachable; }
}
/// <summary>
/// Gets the start column of this <see cref="DebugInfoExpression" />.
/// </summary>
public virtual int StartColumn
{
get { throw ContractUtils.Unreachable; }
}
/// <summary>
/// Gets the end line of this <see cref="DebugInfoExpression" />.
/// </summary>
public virtual int EndLine
{
get { throw ContractUtils.Unreachable; }
}
/// <summary>
/// Gets the end column of this <see cref="DebugInfoExpression" />.
/// </summary>
public virtual int EndColumn
{
get { throw ContractUtils.Unreachable; }
}
/// <summary>
/// Gets the <see cref="SymbolDocumentInfo"/> that represents the source file.
/// </summary>
public SymbolDocumentInfo Document
{
get { return _document; }
}
/// <summary>
/// Gets the value to indicate if the <see cref="DebugInfoExpression"/> is for clearing a sequence point.
/// </summary>
public virtual bool IsClear
{
get { throw ContractUtils.Unreachable; }
}
protected internal override Expression Accept(ExpressionVisitor visitor)
{
return visitor.VisitDebugInfo(this);
}
}
#region Specialized subclasses
internal sealed class SpanDebugInfoExpression : DebugInfoExpression
{
private readonly int _startLine, _startColumn, _endLine, _endColumn;
internal SpanDebugInfoExpression(SymbolDocumentInfo document, int startLine, int startColumn, int endLine, int endColumn)
: base(document)
{
_startLine = startLine;
_startColumn = startColumn;
_endLine = endLine;
_endColumn = endColumn;
}
public override int StartLine
{
get { return _startLine; }
}
public override int StartColumn
{
get { return _startColumn; }
}
public override int EndLine
{
get { return _endLine; }
}
public override int EndColumn
{
get { return _endColumn; }
}
public override bool IsClear
{
get { return false; }
}
protected internal override Expression Accept(ExpressionVisitor visitor)
{
return visitor.VisitDebugInfo(this);
}
}
internal sealed class ClearDebugInfoExpression : DebugInfoExpression
{
internal ClearDebugInfoExpression(SymbolDocumentInfo document)
: base(document)
{
}
public override bool IsClear
{
get { return true; }
}
public override int StartLine
{
get { return 0xfeefee; }
}
public override int StartColumn
{
get { return 0; }
}
public override int EndLine
{
get { return 0xfeefee; }
}
public override int EndColumn
{
get { return 0; }
}
}
#endregion Specialized subclasses
public partial class Expression
{
/// <summary>
/// Creates a <see cref="DebugInfoExpression"/> with the specified span.
/// </summary>
/// <param name="document">The <see cref="SymbolDocumentInfo"/> that represents the source file.</param>
/// <param name="startLine">The start line of this <see cref="DebugInfoExpression" />. Must be greater than 0.</param>
/// <param name="startColumn">The start column of this <see cref="DebugInfoExpression" />. Must be greater than 0.</param>
/// <param name="endLine">The end line of this <see cref="DebugInfoExpression" />. Must be greater or equal than the start line.</param>
/// <param name="endColumn">The end column of this <see cref="DebugInfoExpression" />. If the end line is the same as the start line, it must be greater or equal than the start column. In any case, must be greater than 0.</param>
/// <returns>An instance of <see cref="DebugInfoExpression"/>.</returns>
public static DebugInfoExpression DebugInfo(SymbolDocumentInfo document, int startLine, int startColumn, int endLine, int endColumn)
{
ContractUtils.RequiresNotNull(document, "document");
if (startLine == 0xfeefee && startColumn == 0 && endLine == 0xfeefee && endColumn == 0)
{
return new ClearDebugInfoExpression(document);
}
ValidateSpan(startLine, startColumn, endLine, endColumn);
return new SpanDebugInfoExpression(document, startLine, startColumn, endLine, endColumn);
}
/// <summary>
/// Creates a <see cref="DebugInfoExpression"/> for clearing a sequence point.
/// </summary>
/// <param name="document">The <see cref="SymbolDocumentInfo"/> that represents the source file.</param>
/// <returns>An instance of <see cref="DebugInfoExpression"/> for clearning a sequence point.</returns>
public static DebugInfoExpression ClearDebugInfo(SymbolDocumentInfo document)
{
ContractUtils.RequiresNotNull(document, "document");
return new ClearDebugInfoExpression(document);
}
private static void ValidateSpan(int startLine, int startColumn, int endLine, int endColumn)
{
if (startLine < 1)
{
throw Error.OutOfRange("startLine", 1);
}
if (startColumn < 1)
{
throw Error.OutOfRange("startColumn", 1);
}
if (endLine < 1)
{
throw Error.OutOfRange("endLine", 1);
}
if (endColumn < 1)
{
throw Error.OutOfRange("endColumn", 1);
}
if (startLine > endLine)
{
throw Error.StartEndMustBeOrdered();
}
if (startLine == endLine && startColumn > endColumn)
{
throw Error.StartEndMustBeOrdered();
}
}
}
}
#endif